West Coast Sr Mirrors (DG 5 option)-need special washer

[Henry]

Hi:
I am trying to assemble the parts for the West Coast Sr mirrors (DG 5) option that was available for most of the 70s and 80s...I have the correct mirrors and most of the bracketry but am missing some of the hardware. One part I am missing is a "special washer" that goes between the upper door bracket and the mirror support. The GM parts book describes it as:

Washer, Mirror Support-Spl (25/64" ID x 1" OD x 1/32" thk)

Is this a metal washer or is it plastic or some other material? It is item #13 in the exploded diagram I have attached.

I am also looking for the original GM mirror support....item #15 in the illustration.

Does anyone have an idea on where to get them?

My truck is a 76 C-20 Custom Deluxe.

Regards,
Henry

[OilBurner]

I know the washer is just a metal star washer, any hardware store should have them. As for the support I have no clue